Abstract: This invention relates to compositions containing a sulfur containing antiwear/extreme pressure agent, basic nitrogen compound or a mixture thereof together with a hydrocarbyl mercaptan. The composition may additionally contain a phosphorus or boron antiwear or extreme pressure agent, a dispersant or an overbased metal salt. The invention also relates to lubricants, functional fluids, and concentrates containing the same. Seals, e.g. nitrile, polyacrylate, and fluoroelastomer, in contact with these composition have reduced deterioration. With the use of these compositions, lubricants, and functional fluids, the seals' useful life is extended.

Abstract: Functional fluids characterized as effective over a wide range of temperature including very high temperatures can be prepared, comprising:(A) a major amount of at least one synthetic base oil; and minor amount of(B) at least one phenolic compound selected from the group consisting of(B-1) metal-free, hindered phenols substituted with at least one alkyl group containing at lease about 6 carbon atoms, and alkylene coupled derivatives thereof;(B-2) neutral and basic alkaline earth metal salts of hindered phenols which are not alkylene or sulfur-coupled;(B-3) metal-free alkyl phenol sulfides or neutral and basic alkaline earth metal salts of alkyl phenol sulfides; and(B-4) neutral and basic alkaline earth metal salts of alkylene-coupled phenols; and(C) at least one non-phenolic antioxidant.